The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 14, 2020
Filed:
Sep. 01, 2016
Kabushiki Kaisha Toshiba, Minato-ku, JP;
Shinji Saito, Yokohama, JP;
Tsutomu Kakuno, Fujisawa, JP;
Osamu Yamane, Yokohama, JP;
Akira Tsumura, Yokohama, JP;
KABUSHIKI KAISHA TOSHIBA, Minato-ku, JP;
Abstract
A distributed feedback semiconductor laser of includes a semiconductor stacked body and a first electrode. The semiconductor stacked body includes a first layer, an active layer that is provided on the first layer and is configured to emit laser light by an intersubband optical transition, and a second layer that is provided on the active layer. The semiconductor stacked body has a first surface including a flat portion and a trench portion; the flat portion includes a front surface of the second layer; the trench portion reaches the first layer from the front surface; the flat portion includes a first region and a second region; the first region extends along a first straight line; the second region extends to be orthogonal to the first straight line; and the trench portion and the second region outside the first region form a diffraction grating having a prescribed pitch along the first straight line. The first electrode is provided in the first region.